Everyone rejoices at the arrival of summer, welcoming the chance to cast off drab winter clothes and expose a little flesh. But there’s one section of society that appreciates a bit of sunshine and warm weather more than most - Britain’s 25,000 committed naturists.

For them, going around with no clothes on is a declaration of belief (they refer to non-naturists as “textiles”) and the long winter months, when they make do with occasional indoor events at swimming pools and leisure centres, are frustrating. But come mid-summer, they are in their element, mingling with verve in naturist clubs, beaches and campsites.

Although people have sunbathed and swum naked in secluded places since time immemorial, organised naturism dates from the 1920s, when a spirit of liberation in the post-war years was reflected in the formation of such organisations as the Sunbathing Society and the New Gymnosophy Society. In 1932, George Bernard Shaw, Julian Huxley and Vera Brittain put their names to a letter in The Times calling for proper recognition of the benefits of “airbathing in less than a bathing costume”.

But the practice has never really caught on in the UK, due, no doubt, to most people’s unwillingness to expose their naked selves to strangers, and Britain’s less than clement climate. It might be different if we had fur, feathers or even scales, but there’s something vulnerable about human skin. And then, of course, there’s the question of “public decency”.

There’s disagreement in naturist circles about whether they would really like everyone to go about naked all the time, as part of the movement’s raison d’etre is its defiance of convention. “I don’t agree with them, but some people feel that if everyone joined, we would no longer be an elite,” explains Richard Daniels, president of the Central Council for British Naturism, who also happens to be a policeman.

For him, naturism is about freedom and acceptance. “What most people don’t understand is that naturism is not at all sexual. It is simply to do with feeling comfortable and relaxed about your body. We’re much less judgmental about shapes, sizes and oddities, which means people who have had mastectomies or amputations feel completely unselfconscious with us. And of course, swimming is much nicer without a costume.”

At his local club, in Buckinghamshire, the only clothing rule is that you must be naked to swim - otherwise you can cover up to keep warm or protect yourself from the sun.

It’s unusual for anyone to join a naturist club for “the wrong reasons”, he says. “If they do, they are spotted and weeded out very quickly. At our club, only twice in 20 years has someone has been asked to leave. There was one chap who, having taken his clothes off, kept peeping out from behind his newspaper and ogling people. But that was exceptional. In general I’d say we are kinder and nicer to each other than the rest of society.”

Richard and his wife, Anne, have brought up their three children (now 21, 20 and 15) as naturists with no apparent ill-effects. The oldest has become as committed as his parents and even puts it on his CV, the middle son is no longer interested, and the daughter still goes on naturist holidays with her parents, but has become a “bit wary”.

Mr Daniels says: “As a group, we don’t believe in forcing children to take their clothes off - they have to be comfortable about it. But they usually are once they see all the other children running about naked.”

As the only naturist at his police station, PC Daniels comes in for a certain amount of ribbing (his nickname is Dickie-no-clothes), but over the years he has come across many other naturist PCs.

The movement is also home to a great many teachers, although most are wary of being interviewed, even anonymously. Rex Watson, who edits the magazine British Naturism, explains: “Teachers are petrified of being identified as naturists by their pupils. My 13-year-old step-daughter and her class teacher were appalled when they bumped into each other at the club last summer. But eventually both realised it was a stand-off and stopped worrying. Teachers may also fear that parents and school authorities will see their involvement in naturism as ‘undesirable’. You can’t really discount this fear as many misconceptions about naturism remain.”

This was certainly the experience of Anne Summerhill, an education support assistant at a special needs school in Wiltshire. “The local paper carried an article about me. Some parents were so horrified that they threatened a petition,” she recalls. But the crisis blew over, and 45-year-old Anne continues to be open about her naturism. “What annoyed me most was the implication that I must be immoral. People are quick to equate nakedness with sex, but there’s no swinging scene in naturism. It’s very family-oriented.”

Although her four sons are no longer naturists, she believes they have naturism to thank for the way they took puberty in their stride. But the family has never belonged to a club, preferring to sunbathe naked in their back garden and take naturist holidays. “For all I know, the neighbours think we’re complete nutters, but they must have caught sight of me several times over the yearsand they’ve never said anything. Quite honestly I feel much less self-conscious naked than in a bikini, because I’ve got the kind of stomach that hangs over things.”

The wonderful thing about naturist holidays, she says, is that without clothes everyone is equal. “We met this couple in a naturist village in Cap D’Agde and really enjoyed their company. Then we bumped into them fully clothed at the airport and realised they were the sort of people we’d normally give a wide berth, because they looked a bit hippyish and unwashed. It just shows how much we judge people by their clothes.”

In reality, she reveals, many people at naturist camps wear clothes in the evening. “Only the purists insist on being naked all the time. I like to put on some make-up and get dressed up in the evening.”

Christine Ashford was a primary teacher for 20 years before becoming general secretary of the Naturist Foundation in Kent. “When I was teaching, it wasn’t common knowledge that I was a naturist, although if the conversation came round to holidays or swimming, I’d probably mention it. But I’d keep off the subject if I thought the people I was with wouldn’t understand,” she admits.

“People have such odd ideas about naturism, especially the supposed correlation between nakedness and sex. Naturism is about relaxation and freedom, not sex. When I’m dressed, I dress conventionally - no plunging necklines or short skirts. I just like the feeling of wearing no clothes when it’s warm. But it’s not an obsession. We don’t turn up the central heating in winter so we can walk about with no clothes on, and even when it’s warm I usually put something on at around 9pm. I also wear gardening gloves to garden and strong shoes to mow the lawn.”

Christine’s husband, John, works as an IT technician at the Priory School in Orpington, Kent, where their youngest son, Peter, is a pupil. “I’m often in the local paper,” says Christine, “so there can’t be anyone in that school who doesn’t know the Ashford family are naturists. Fortunately, they are completely relaxed about it.”

Central Council for British Naturism, tel:01604 620361Naturist Foundation, tel: 01689 871200